S
M
T
W
T
F
S
26
49°
30°
27
51°
31°
28
52°
33°
29
60°
29°
30
66°
28°
1
71°
30°
2
72°
36°
3
73°
33°
4
65°
47°
5
59°
33°
6
67°
29°
7
68°
44°
8
70°
38°
9
70°
43°
10
73°
37°
11
74°
41°
12
76°
36°
13
65°
43°
14
58°
45°
15
60°
40°
16
48°
33°
17
53°
32°
18
58°
29°
19
58°
35°
20
59°
35°
21
62°
29°
22
68°
40°
23
74°
37°
24
77°
41°
25
83°
37°
26
78°
51°
27
78°
54°
28
89°
56°
29
79°
51°
30
67°
47°
31
55°
49°
1
55°
46°
2
61°
44°
3
69°
46°
4
68°
46°
5
71°
46°
6
68°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Big Arm
Big Arm's May 2026 forecast shows daily high temperatures ranging from 55° to 71°, with overnight lows between 44° and 49°. The average high for May is 64° with an average low of 46°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Big Arm. See also: June | July | August.